Re: [HACKERS] Increase Vacuum ring buffer.

On Thu, Jul 20, 2017 at 3:04 PM, Stephen Frost <sfrost@snowman.net> wrote:
> I agree that it's a common problem for VACUUM to go too fast, or for
> VACUUM to go too slow, but that's really what the vacuum_cost_limit
> mechanism is for.

I think that's a valid point.  There are also other concerns here -
e.g. whether instead of adopting the patch as proposed we ought to (a)
use some smaller size, or (b) keep the size as-is but reduce the
maximum fraction of shared_buffers that can be consumed, or (c) divide
the ring buffer size through by autovacuum_max_workers.  Personally,
of those approaches, I favor (b).  I think a 16MB ring buffer is
probably just fine if you've got 8GB of shared_buffers but I'm
skeptical about it when you've got 128MB of shared_buffers.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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